org.jboss.tm
Class TransactionLocal

java.lang.Object
  org.jboss.tm.TransactionLocal

public class TransactionLocal
extends Object

A TransactionLocal is similar to ThreadLocal except it is keyed on the Transactions. A transaction local variable is cleared after the transaction completes.

Version:

$Revision: 57208 $

Author:

Dain Sundstrom, Bill Burke

Field Summary

protected TransactionLocalDelegate	delegate The delegate
protected TransactionManager	transactionManager The transaction manager is maintained by the system and manges the assocation of transaction to threads.

Constructor Summary

TransactionLocal()
Creates a thread local variable.

TransactionLocal(TransactionManager tm)
Creates a transaction local variable.

Method Summary

protected boolean	containsValue(Transaction tx) does Transaction contain object?
Object	get() Returns the value of this TransactionLocal variable associated with the thread context transaction.
Object	get(Transaction transaction) Returns the value of this TransactionLocal variable associated with the specified transaction.
Transaction	getTransaction()
protected Object	getValue(Transaction tx) get the transaction local value.
protected void	initDelegate() Initialise the delegate
protected Object	initialValue() Returns the initial value for this thransaction local.
void	lock() Lock the TransactionLocal using the current transaction
void	lock(Transaction transaction) Lock the TransactionLocal using the provided transaction
void	set(Object value) Sets the value of this TransactionLocal variable associtated with the thread context transaction.
void	set(Transaction transaction, Object value) Sets the value of this TransactionLocal variable associtated with the specified transaction.
protected void	storeValue(Transaction tx, Object value) put the value in the TransactionImpl map
void	unlock() Unlock the TransactionLocal using the current transaction
void	unlock(Transaction transaction) Unlock the ThreadLocal using the provided transaction

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

transactionManager

protected final TransactionManager transactionManager

The transaction manager is maintained by the system and manges the assocation of transaction to threads.

delegate

protected TransactionLocalDelegate delegate

The delegate

Constructor Detail

TransactionLocal

public TransactionLocal()

Creates a thread local variable.

Throws:

IllegalStateException - if there is no system transaction manager

TransactionLocal

public TransactionLocal(TransactionManager tm)

Creates a transaction local variable. Using the given transaction manager

Parameters:

tm - the transaction manager

Method Detail

lock

public void lock()
          throws InterruptedException

Lock the TransactionLocal using the current transaction

WARN: The current implemention just "locks the transactions"

Throws:

IllegalStateException - if the transaction is not active

InterruptedException - if the thread is interrupted

lock

public void lock(Transaction transaction)
          throws InterruptedException

Lock the TransactionLocal using the provided transaction

WARN: The current implemention just "locks the transactions"

Parameters:

transaction - the transaction

Throws:

IllegalStateException - if the transaction is not active

InterruptedException - if the thread is interrupted

unlock

public void unlock()

Unlock the TransactionLocal using the current transaction

unlock

public void unlock(Transaction transaction)

Unlock the ThreadLocal using the provided transaction

Parameters:

transaction - the transaction

initialValue

protected Object initialValue()

Returns the initial value for this thransaction local. This method will be called once per accessing transaction for each TransactionLocal, the first time each transaction accesses the variable with get or set. If the programmer desires TransactionLocal variables to be initialized to some value other than null, TransactionLocal must be subclassed, and this method overridden. Typically, an anonymous inner class will be used. Typical implementations of initialValue will call an appropriate constructor and return the newly constructed object.

Returns:

the initial value for this TransactionLocal

getValue

protected Object getValue(Transaction tx)

get the transaction local value.

storeValue

protected void storeValue(Transaction tx,
                          Object value)

put the value in the TransactionImpl map

containsValue

protected boolean containsValue(Transaction tx)

does Transaction contain object?

get

public Object get()

Returns the value of this TransactionLocal variable associated with the thread context transaction. Creates and initializes the copy if this is the first time the method is called in a transaction.

Returns:

the value of this TransactionLocal

get

public Object get(Transaction transaction)

Returns the value of this TransactionLocal variable associated with the specified transaction. Creates and initializes the copy if this is the first time the method is called in a transaction.

Parameters:

transaction - the transaction for which the variable it to be retrieved

Returns:

the value of this TransactionLocal

Throws:

IllegalStateException - if an error occures while registering a synchronization callback with the transaction

set

public void set(Object value)

Sets the value of this TransactionLocal variable associtated with the thread context transaction. This is only used to change the value from the one assigned by the initialValue method, and many applications will have no need for this functionality.

Parameters:

value - the value to be associated with the thread context transactions's TransactionLocal

set

public void set(Transaction transaction,
                Object value)

Sets the value of this TransactionLocal variable associtated with the specified transaction. This is only used to change the value from the one assigned by the initialValue method, and many applications will have no need for this functionality.

Parameters:

transaction - the transaction for which the value will be set

value - the value to be associated with the thread context transactions's TransactionLocal

getTransaction

public Transaction getTransaction()

initDelegate

protected void initDelegate()

Initialise the delegate